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Comments:
<NoorulIslaam> it's not a pancake
<NoorulIslaam> it's a straight line
<JohnFlux> it's a pancake looking at it from above
<NoorulIslaam> take a meter stick
<NoorulIslaam> now move it sideways
<NoorulIslaam> that's your linearly polarized photon
<JohnFlux> if our one meter wide photon is moving forward in a vacumn, then one period would also be a meter right?
<NoorulIslaam> take a pie plate, and move it across like you're about to pie someone...that's a circularly polarized photon
<JohnFlux> right, but take the pie plate and hold it like you'll frizzbie it
<JohnFlux> i'm thinking like that
<JohnFlux> linearly polarised
<JohnFlux> but also consider it's size forwards
<JabberWalkie> NoorulIslaam: isn't that just a bunch of linearly polarized photons that are superpositioned?
<NoorulIslaam> JabberWalkie i think of it the other way
<JohnFlux> its
<JohnFlux> JabberWalkie: can you have a circularly polarised wave with the energy of just one photon?
<NoorulIslaam> the linear photon is a superposition of circular photons
<JohnFlux> NoorulIslaam: then can you have a linearly polarised wave with the energy of just one photon?
<NoorulIslaam> JohnFlux no, it doesn't work like that
<NoorulIslaam> JohnFlux of course
<NoorulIslaam> JohnFlux energy is related to frequency
<JohnFlux> take the meter stick you were using
<NoorulIslaam> ok
<JohnFlux> now imagine that it had rotational momentum
<NoorulIslaam> ok
<JohnFlux> that's not the same as it being a pie dish
<JohnFlux> i'm talking about it being linear
<NoorulIslaam> yeah
<JohnFlux> but rotating through time
<NoorulIslaam> ok
<JohnFlux> right?
<NoorulIslaam> yeah it's no longer linear
<JohnFlux> now, can that happen
<JohnFlux> why is it not linear. at any moment of time, it's linear
<JohnFlux> freeze time, and it's a meter stick still
<NoorulIslaam> of course
<NoorulIslaam> but since it's spinning
<NoorulIslaam> you'll never measure it as linear
<JohnFlux> whereas with our pie dish, freeze time and it's still a pie dish
<NoorulIslaam> it'll always be measured as circular
<NoorulIslaam> forget the pie dish
<JohnFlux> what's the difference between our pie dish and our spinning meter stick?
<NoorulIslaam> bad example
<JabberWalkie> JohnFlux: freezing time dosn't get rid of the angular momentum inherrent in the photon
<JohnFlux> so is it always a spinning meter stick?
<JohnFlux> JabberWalkie: right
<NoorulIslaam> actually no
<NoorulIslaam> forget the meter stick
<NoorulIslaam> it's always a pie dish
<JohnFlux> bah heheh
<NoorulIslaam> even when it's linear
<JohnFlux> so what happens when it's linearly polarised?
<NoorulIslaam> now, mark a spot on the rim of the pie dish
<NoorulIslaam> that's your electric field vector
<JohnFlux> right
<JohnFlux> okay
<NoorulIslaam> if you rotate the pie dish 180 degrees, you reverse the electric field of the photon
<JohnFlux> right
<NoorulIslaam> if the pie dish isn't spinning
<NoorulIslaam> then the polarization is linear
<NoorulIslaam> because the orientation of the electric field traces out a sine wave that is always inside a plane that doesn't change orientation
<NoorulIslaam> if you spin the pie dish, you get an electric field that traces out a corkscrew shape as it travels forward
<JohnFlux> imagine a big polarising filter, but the lines are still say 1mm apart
<JohnFlux> can you get a 1 meter big radio wave through that?
<Shray> hm - quick refresher question - how do you figure out how many moles of argon are present in 100g of argon ?
<JohnFlux> if you get the polarisation right?
<NoorulIslaam> JohnFlux the radio wave would probably tunnel right through it
<NoorulIslaam> losing a bit of energy in the process
<JohnFlux> NoorulIslaam: what if it's a grid instead?
<JohnFlux> like a #
<NoorulIslaam> a faraday cage?
<JohnFlux> right
<JohnFlux> then it can't get through, right?
<NoorulIslaam> so if it's made of metal
<JohnFlux> right
<NoorulIslaam> the radio wave would get absorbed and converted to electricity
<NoorulIslaam> which if it's grounded
<NoorulIslaam> would be conducted away
<JohnFlux> why can this 1 meter big pie dish radio wave photon manage to get through my 1mm big grid?
<JohnFlux> s/grid/polariser/
<JohnFlux> so when it looks like ==
<NoorulIslaam> sort of the same way low frequency sound waves manage to travel through your door
<JohnFlux> I'm comparing two things: a = object and a # object
<JohnFlux> but the faraday cage can stop the light a lot better than the parallel lines alone
<JohnFlux> hmm okay wait
<NoorulIslaam> it doesn't stop light
<JohnFlux> wrong approach i think
<JohnFlux> how does a polariser work?
<NoorulIslaam> light is small enough to fit through the faraday cage
<NoorulIslaam> a 1mm grid would work for microwaves i think
<NoorulIslaam> it's atoms' electric field is aligned in a particular direction
<JohnFlux> NoorulIslaam: "light" included my radio wave hehe
<JohnFlux> a polariser is just a bunch of wires looking like =
<JohnFlux> all the wires parallel
<JohnFlux> right?
<NoorulIslaam> so photons whose electric field is in that direction can p***
<NoorulIslaam> polarizer aren't metal i think
<JohnFlux> if the atoms electric fields weren't aligned, what would happen?
<NoorulIslaam> you would get a less effective polarizer
<JohnFlux> would the light just p*** uneffected?
<NoorulIslaam> if the atoms were completely random
<NoorulIslaam> then the light would p*** unaffected
<JohnFlux> hmm
<JohnFlux> light is too wierd
<JohnFlux> NoorulIslaam: thanks for taking the time and being patient
<JohnFlux> :)
<NoorulIslaam> it's not weird
<darkgreen> http://en.wikipedia.org/wiki/Polarizer "Note that the polarization direction is perpendicular to the wires; the naive concept of a wave "slipping through" the gaps between the wires is incorrect."
<NoorulIslaam> it acts like any other wave would
<NoorulIslaam> with the notable difference that it exists in 4-dimensions instead of 3
<JohnFlux> 4?
<NoorulIslaam> yeah
<JohnFlux> hmm time
<NoorulIslaam> space-time
<NoorulIslaam> instead of just space
<JohnFlux> well doesn't a water wave as well?
<NoorulIslaam> not the wave itself
<NoorulIslaam> for example, the electric field has an accompanying magnetic field
<NoorulIslaam> thanks to it's 4-dimensional nature
<NoorulIslaam> the water wave has no such counterpart
<JohnFlux> isn't the counterpart gravitational potential or something
<JohnFlux> hmm
<JohnFlux> the magnetic wave stores energy while the electric field becomes zero
<JohnFlux> hmm in a water wave that would be the forces between the atoms
<JohnFlux> whatever the force is that holds water atoms together
<JohnFlux> weak nuclear?
<NoorulIslaam> the force between the atoms is the electromagnetic force
<NoorulIslaam> the nuclear forces only exist within the nucleaus
<NoorulIslaam> and play not matter in atom-to-atom interactions
<NoorulIslaam> not matter=no part
<NoorulIslaam> hmm...
<JohnFlux> ah right sorry
<fritobandito> what about plasma?
<NoorulIslaam> back...
<NoorulIslaam> what about plasma?
<JabberWalkie> so how about that plasma??
<JabberWalkie> isn't it a big ol' lump of high temperature ionized matter!
<JabberWalkie> wooooo dogy!
<NoorulIslaam> the electromagnetic force would be too strong to let the nuclear forces do anything
<NoorulIslaam> unless the temperature is extremely high
<NoorulIslaam> like in fusion reactors :)
<fritobandito> and then you've got ur neutron stars
<fritobandito> they're just dope
<NoorulIslaam> yeah
<NoorulIslaam> a neutron star is a humongo nucleaus
<NoorulIslaam> nucleus*
<Manyfold> hello punks
<fritobandito> quantum encryption through entangled photons
<JV625> Does anyone know why the resistance between the soucr and drain on a Surface Mount Field Effect Transistor would be far less than its equivalent in a thru-hole package?
<JabberWalkie> JV625: try #electronics
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